We just substitute in -12 for x in each one and see if it's true
2(-12)+6 = -24 + 6 = -18, not 30, NOPE
-0.25(-12) - 1 = 3-1 = 2, that worked, CHECK ME
-12 - 8 = -20, CHECK ME
-35(-12) +2 = 422, not -515, NOPE
3(-12+25)=3(13)=39, CHECK ME
Answer:
Step-by-step explanation:
To use the quadratic formula, we must write the quadratic in standard form, viz:
2x^2 - 4x + 7 = 0
Start by calculating the discriminant. That's b^2 - 4(a)(c). Here,
a = 2, b = -4 and c = 7, and so the discriminant for this particular problem is
(-4)^2 - 4(2)(7), or 16 - 56, or 40.
Recall that a positive discriminant indicates two real, unequal roots.
Now we write out the whole quadratic formula, with the appropriate constants inserted (see above):
-(-4) ± √40 4 ± (√4)(√10) 4 ± 2√10
x = --------------------- = ---------------------- = ---------------
2(2) 4 4
2 ± √10
which reduces to x = --------------
2
Answer:
D. 2.69 lb is your answer
13vases=34.97lb
1 vase=34.97/13=2.69lb
Answer:
Step-by-step explanation:
39.19
